Patent GB-769348-A (GB)
Title: Improvements in or relating to conveyor systems
Inventor: BURROWS ARTHUR THOMAS CHARLES
IPC: F16D9/06
Filed: 1954-12-15
Abstract: 769,348. Endless chain conveyers. KING, Ltd., G. W. Nov. 23, 1955 [Dec. 15, 1954], No. 36322/54. Class 78 (1). In a conveyer system, e.g. as described in Specification 731,455, having two parallel chains travelling at different speeds in a common horizontal plane to support loaded pallets or trays which can be coupled at will to either of the chains, the drive sprockets for the two chains are driven from a common motor, each sprocket including a shear pin adapted upon failure to stop the driving motor, and an indicator device including an epicyclic gear assembly, is interposed between the fast sprocket and a clutch on its shaft, the arrangement being such that if the shear pin on the slow sprocket fails it will be possible by declutching the fast sprocket and by means of the indicator device to so adjust the fast sprocket after insertion of a new shear pin in the slow sprocket as to take care of any overrunning of the fast chain which took place on stoppage of the drive. As shown, the fast sprocket shaft 11 is driven by the motor and drives the slow sprocket shaft (not shown) through gearing 12. The clutch comprises a sleeve 13 slidable on splines on shaft 11. Two opposed pairs of arms 14 are welded to the sleeve and carry sleeves in which are secured pins 15 which normally engage in holes drilled in the fast sprocket 10, which is loosely mounted on shaft 11. The pins are retained in engaged position by a springy collar 16 interposed between the sleeve 13 and a bush 17 secured to the shaft. The indicator device comprises internally -toothed gear-rings 18, 19 rotatable on discs 23, 24, which are secured to a sleeve 18<1> secured to shaft 11. Gear ring 19 is fixed in position relative to sprocket 10 by pins 19<1>. Ring 19 has one more tooth than ring 18. The rings are geared together by a composite pinion 21, 22 journalled in the discs 23, 24, part 22 having one more tooth than part 21. The rings 18, 19 have respective markers 25, 26 which are normally opposite one another. If the shear pin on the slow sprocket fails and stops the driving motor the clutch is first uncoupled by opening the collar 16 and sliding it on to the bush 17, and relieving the driving pressure on shaft 11 to enable sleeve 13 to be slid away from the fast sprocket. Shaft 11 is now driven backwards to re-align the slow sprocket for insertion of a fresh shear pin. This causes the markers 25, 26 to move out of alignment, so that it is then necessary to drive shaft 11 forwards to allow for the over-run of the fast sprocket until the markers are again opposite one another, whereupon the clutch is then re-engaged with the two conveyer chains in their original relationship. The conveyer may include a second slow chain, e.g. at a junction, and the corresponding second drive sprocket will also have a shear pin, and be driven from the same driving motor. In order to avoid reversal of this second slow chain during replacement of the shear pin on the first slow chain sprocket a one-way clutch (Figs. 3 and 4, not shown) is interposed in the drive to the second chain.